Mayor Bob Filner’s battle to stay in office amid sexual harassment allegations is being fought on multiple fronts with a recall movement gaining steam and the creation Friday of a hotline for his accusers to notify authorities of possible criminal misconduct.

The embattled mayor has also become the subject of increasing national ridicule as comedian Stephen Colbert skewered him during his late-night show.

Filner has made it clear he doesn’t plan to resign and has all but dared his unidentified accusers to file a formal complaint so he can get due process. Now those alleged victims know the proper venue to submit their grievances.

The San Diego County Sheriff’s Department announced Friday it would be the lead investigative agency for any complaints against Filner and set up a hotline — 619-481-0220 — for alleged victims to call. The department would then forward information to the state Attorney General’s Office for possible prosecution.

Filner issued a statement late Friday in response to the hotline announcement.

“I very much welcome the fact that some of these allegations will finally be addressed by an appropriate investigative authority rather than by press conference and innuendo,” Filner said. “As I have stated before, everyone deserves due process and I am encouraged an effort to implement that has begun.”

In an interview, Sheriff Bill Gore said the county’s law enforcement leaders — including San Diego Police Chief Bill Lansdowne, District Attorney Bonnie Dumanis and officials from the Attorney General’s Office — met to discuss the allegations and how to handle a potential investigation against Filner should it come to that. The group took into consideration Filner’s position within the community, he said.

Gore called the situation “extremely sensitive” and his agency would not release details to the public while any investigation was ongoing.

“It’s obviously of concern, the allegations which people have read in the paper,” Gore said. “The public safety leadership in the community discussed it and feel this is the appropriate way to address it, so all parties concerned are treated fairly.”

Under state law, victims of sexual assault may be given anonymity and may be accompanied by an advocate while being interviewed, the Sheriff’s Department said. Capt. Duncan Fraser, in charge of the department’s central investigations division, would oversee any inquiries.

No formal complaints or lawsuits had been lodged against Filner as of late Friday.

Meanwhile, the nascent movement to recall Filner picked up momentum Friday as proponents held a rally outside City Hall to sign up volunteers for the coming petition drive.

More than 80 people attended the event led by talk radio personality Mike Slater and land-use consultant Michael Pallamary, who has led the only other successful recall bid in city history.

“Welcome to step one of our effort to recall our mayor, Bob Filner,” Slater said. “ …This is not about party. This is about principle. This is not about left or right. This is about right or wrong. And this certainly is not a Republican or GOP-led effort, not by any means. This is a San Diego-led effort.”